SECTION CONCRETE PAVING

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1 PART 1 GENERAL 1.1 SECTION INCLUDES SECTION CONCRETE PAVING A. Extent of concrete curbs, walks, and paving as show on drawings B. Earthwork and prepared sub-base C. Concrete and related materials D. Joint Fillers and Sealers 1.2 QUALITY ASSURANCE A. Comply with local governing regulations if more stringent than herein specified. 1.3 JOB CONDITIONS A. Maintain access for vehicular and pedestrian traffic as require for other construction activities. 1.4 LEED COMPLIANCE A. The District has determined that projects shall be constructed complying with Leadership in Energy and Environmental Design (LEED) requirements as promulgated in the document titled: LEED Reference Guide for Green Building Design and Construction, For the Design, Construction and Major Renovations of Commercial and Institutional Buildings, Including Core & Shell and K-12 School Projects, 2009 Edition. B. The District goal is LEED Silver Certification for all major projects. Certification is not required for small projects consisting only of minor paving work. C. Investigate the potential LEED compliance areas as listed below for construction in accordance with this specification. 1. SS Prerequisite 1 Construction Activity Pollution Prevention 2. MR Credit 2 Construction Waste Management 3. MR Credit 3 Materials Reuse 4. MR Credit 5 Regional Materials PART 2 PRODUCTS 2.1 MATERIALS A. Form shall be steel, wood, or other suitable material of size and strength to resist movement during concrete placement and to retain horizontal and vertical alignment until removal. 1. Use straight forms, free of distortion and defects. B. Use flexible spring steel forms or laminated boards to form radius bends as required. C. Coat forms with a non-staining form release agent that will not discolor or deface the surface of the concrete. D. No Earth Forming allowed. E. Concrete Materials: Comply with requirements of applicable sections for concrete materials, admixture, bonding materials, curing materials, and others as required. Architect s Project Number of 5 Concrete Paving

2 F. Expansion Joint Materials: Comply with requirements of Sections for performed expansion joint fillers and sealers. 2.2 CONCRETE MIX, DESIGN AND TESTING A. Comply with requirements of applicable Section for concrete mix design, sampling and testing, and quality control, and as herein specified. B. Design mix to produce standard-weight concrete consisting of portland cement, aggregate, airentraining admixture and water to produce the following properties: C. Compressive Strength: 3000 psi, minimum at 28 days D. Slump Range: 2" to 4" E. Air Content: 5% to 8% PART 3 EXECUTION 3.1 INSPECTION A. Examine the areas and conditions for the installation of concrete curbs, walks, and paving, if there are conditions detrimental to the proper and timely completion; notify the A/E in writing immediately. B. Do not proceed with work until unsatisfactory conditions are corrected. 3.2 SURFACE PREPARATION A. Remove loose material from the compacted subgrade surface immediately before placing concrete. B. Proof-roll prepared subgrade surface to check for unstable areas and need for additional compaction. C. Do not begin paving work until such conditions correct and ready to receive paving (95%, modified proctor). 3.3 FORM CONSTRUCTION A. Set forms to the required grades and lines, rigidly braced and secured. Install sufficient quantity of forms to allow continuous progress of work and so that forms can remain in place at least 24 hours after concrete placement. B. Check completed formwork for grade and alignment to the following tolerances: C. Top of forms not more than 1 / 8 " in 10' deviation in alignment D. Vertical face on longitudinal axis, not more than ¼" in 10' E. Clean forms after each use and coat with form release agent as often as required to ensure separation from concrete without damage. 3.4 REINFORCEMENT A. Use fibermesh concrete unless otherwise noted, following the requirements of Section "FIBROUS CONCRETE REINFORCING". 3.5 CONCRETE PLACEMENT A. General: Comply with the requirements of Sections for mixing and placing concrete, and as specified. Architect s Project Number of 5 Concrete Paving

3 B. Do not place concrete until subgrade and forms are checked and Architect approves for line and grade. 1. Moisten subgrade if require to provide a uniform dampened condition at the time concrete is placed. 2. Do not place concrete around manholes or other structures until they are at required finish elevation and alignment. C. Place concrete using methods, which prevent segregation of mix. 1. Consolidate concrete along face of forms and adjacent to transverse joints with an internal vibrator. 2. Keep vibrator away from joint assemblies, reinforcement, or side forms. 3. Use only square-faced shovels for hand spreading and consolidation. 4. Consolidate with care to prevent dislocation of reinforcing, dowels, and joint devices. D. Deposit and spread concrete in continuous operation between transverse joints, as far as possible. 1. If interrupted for more than ½- hour, place a construction joint. E. Curbs and Gutters: 1. Contractor, with the Architect's approval, may use an automatic machine for curb and gutter placement. 2. If machine placement is used, submit revise mix design and laboratory test results, which meet or exceed minimums specified. 3. Machine placement must produce curbs and gutters to required cross-section, lines, grades, finish, and jointing as specified for formed concrete. 4. If results are not acceptable, remove and replace with formed concrete as specified. 5. Do not extrude curbs on bituminous paving. 3.6 JOINTS A. General: Construct expansion, weakened-plane (contraction), and construction joints true-to-line with face perpendicular to surface of the concrete, unless otherwise indicated. 1. Construct transverse joints at right angles to the centerline, (distance equal to width) unless otherwise indicated. B. Weakened-plane (Contraction) Joints: Provide weakened-plane (contraction) joints, sectioning concrete into areas as shown on the drawings or every ten linear feet for curbs. 1. Construct weakened-plane joints for a depth equal to at least ¼ of the concrete thickness. C. Sawed Joints: Form weakened-plane joints using powered saws equipped with shatterproof abrasive or diamond-rimmed blades. 1. Cut joints into hardened concrete as soon as surface will not be torn, abraded or otherwise damaged by cutting action, but no latter than 48 hours. D. Construction Joints: Place construction joints at end of all pours and locations where concrete placement operations stop for a period of more than ½- hour, except where such pours terminate at expansion joints. E. Construct joints as shown or, if not shown, use standard metal key-way section forms. F. Expansion Joints: Provide pre-molded joint filler for expansion joints abutting concrete curbs, catch basins, manholes, inlets, structures, walks, buildings and other fixed objects, and changes in direction, and as shown on plans. G. Locate expansion joints in pavement vehicle traffic lane 20'-0" o.c., unless otherwise indicated. H. Locate expansion joints the length of the sidewalk 48'-0 o.c., unless otherwise indicated I. Extend joint fillers full-width and depth of joint, and not less than ½" or more than 1", and 1" below finished surface for joints sealer. J. Provide dummy joints in sidewalk slabs 6' o.c., joints may be tool-struck or saw cut. Architect s Project Number of 5 Concrete Paving

4 3.7 CONCRETE FINISHING A. After striking-off and consolidating concrete, smooth surface by screeding and floating. 1. Use hand methods only where mechanical floating is not possible. 2. Adjust floating to compact surface and produce a uniform texture. B. After floating, test surface for trueness with a ten-foot straight edge. 1. Distribute concrete as required to remove surface irregularities, and re-float repaired areas to provide a continuous smooth finish. C. Work edges of slabs, gutters, back top edge of curb, and formed joints with an edging tool, and round to ½" radius, unless otherwise indicted. Eliminate any tool marks on concrete surface. D. After completion of floating and when excess moisture or surface sheen has disappeared, complete surface finishing, as follows: E. Broom finish by drawing fine-hair broom across concrete surface perpendicular to line of traffic. 1. Repeat operation if required to provide a fine line texture acceptable to Architect. F. Do not remove forms for 24 hours after placing concrete. 1. After form removal, clean ends of joints and point-up any minor honeycombed areas. 2. Remove and replace areas or section with major defects, as directed by Architect. 3.8 CURING A. Protect and cure finished concrete paving, complying with applicable requirements of Division 3 Concrete, using moist-curing methods for initial curing whenever possible. 3.9 REPAIRS AND PROTECTIONS A. Repair or replace broken or defective concrete, as directed by Architect. B. Drill test cores when directed by Architect, when necessary to determine magnitude of cracks or defective areas. 1. Fill drilled core holes in satisfactory pavement areas with portland cement concrete bonded to pavement with suitable bonding agent. C. Protect concrete from damage until acceptance of work. 1. Exclude traffic from pavement for at least 14 days after placement. 2. Once construction traffic resumes, maintain pavement as clean as possible by removing surface stains and spillage of materials as they occur. D. Sweep concrete pavement as wash free of stains, discolorations, dirt, and other foreign material just prior to final inspection. E. Repair/Replace existing sidewalks adjacent to property and on property if broken CONCRETE THICKNESS A. Sidewalks shall be 4" thick (6"at driveways) on 4" compact subgrade minimum 6' wide, with psi fiber mesh reinforcement. 1. Slopes between 1:12 and 1:20 indicate accessible ramps and shall comply with the requirements of FBC-Accessibility. 2. Cross slopes on sidewalks shall be a maximum of 1: Extend curbs/sidewalks a minimum 24" from covered walkway columns. 4. Provide raised sidewalks or curbs to separate students from vehicle traffic. B. Concrete Pavement for vehicle traffic areas shall be a minimum 6" thick 3000 psi concrete with 6" x 6" x #6 x #6 welded wire mesh 2" from the bottom of slab on 6" limerock base. 1. Slope concrete 1 / 8 " per foot. Architect s Project Number of 5 Concrete Paving

5 C. Provide accessible ramps meeting the requirements of FBC-Accessibility, at the following location. Flush curbs and bollards not allowed. 1. All crosswalks (including perimeter sidewalks) 2. Bus drop-off area, one per 100 linear feet of drop-off area (minimum two) 3. Parent drop-off area, two places, and one shall meet the requirements of a passenger vanloading zone per FBC-Accessibility. 4. Accessible parking areas and main entrance END OF SECTION Architect s Project Number of 5 Concrete Paving